Centrifugal cleaner for air filters



Jan. 18, 1955 w F. BUCK ETAL 2,699,793

CENTRIF'UGAL CLEANER FOR AIR FILTERS Filed Oct. 4, 1949 2 Sheets-Sheet 1 IN VEN TOR-5- WFZOg/d Ewe/o BYEaZp/z Z 77302726216, 6% 44%, $4M, wm

Jan. 18, 1955 w F. BUCK EIAL CENTRIFUGAL CLEANER FOR AIR FILTERS 2 sneets-snet 2 Filed Oct. 4, 1949 United States Patent CENTRIFUGAL CLEANER FOR AIR FILTERS W. Floyd Buck and Ralph I. Thomas, Lincoln, Nehru, as-

signors to a partnership composed of said Buck, said Thomas, Henry H. Urbach, Evanston, Ill., and Charles E. Melker, Lincoln, Nebr.

Application October 4, 1949, Serial No. 119,548

3 Claims. (Cl. 134-443) This invention relates to a process for cleaning filters and apparatus therefor. More particularly, it relates to a process and apparatus for cleaning filters which are substantially fiat or cylindrical, such as the air filters currently used on diesel locomotives.

Previously used methods of cleaning filters of this type, whether of the substantially flat or cylindrical form, have required three separate containers, a bake oven and overhead hoists. In addition, the cleaning operation, up until now, has consumed about 6 hours per filter. The present process and apparatus which are the subject of this application permit the cleaning and oiling of filters of the general type described, in a single container and .in a plurality of steps requiring a total of approximately 2 minutes per filter.

This new and improved process comprises disposing such filters symmetrically about a common axis of rotation, the fiat filters being disposed with their intake sides out substantially parallel to this axis and the cylindrical filters being disposed so that the longitudinal axis thereof is coincident with this axis of rotation. When so disposed, the filters are then rotated as a unit about the axis of rotation at a relatively high speed, and while being so rotated are brought into association with a plurality of liquid and gaseous agents under pressure.

The actual cleaning steps which have been found to be preferable in the carrying out of this process while the filters are being rotated as described within a suitable housing are: (l) washing the filters with water substantially at the boiling point; (2) washing with a suitable hot solvent, such as a caustic cleaner and water; (3) rinsing with hot water substantially at the boiling point; (4) blowing off and/or drying all remaining liquid with compressed air; (5) spraying with a light oil; and (6) blowing oif surplus oil with compressed air. a

It is therefore an object of this invention to provide a process and apparatus which will permit the rapid cleaning of a plurality of filters both of substantially fiat and cylindrical form in a single container by the rapid rotation of said filter-s and the simultaneous application in the proper sequence of various liquids thereto in the form of a plurality of very thin streams.

It is a further object to provide a process and apparatus of the character described which will accommodate a plurality of substantially flat filters at the same time, and which will permit the use of a desirable centrifugal action in conjunction with a spraying action on both cylindrical and substantially flat filters.

Another object to provide an apparatus which permits the various steps necessary for thorough cleaning of filters to be carried out in the same container, and which also permits the introduction of the various fluids utilized into this single container through a common manifold.

Still another object is to provide such a process and apparatus which will enable the recovery of certain of the liquids so that they may be recycled.

Further objects and advantages of thisinvention will become evident as the description proceeds and from an examination of the accompanying drawings which illustrate one embodiment of the invention and in which similar numerals refer to similar parts throughout the several views.

in the drawings:

Figure l is a side elevation partly in vertical crosssection of one form of apparatus embodying the invention;

Figure 2 is a horizontal sectional view, from above, of

the main portion of the apparatus shown in Figure 1, the section being taken along line 2--2 of that figure; and

Figure 3 is a somewhat diagrammatical representation of the manifold, oil pump and hoist control valve which are pormally associated with the apparatus shown in Figure Referring now to Figures 1 and 2, the main components of the apparatus may be mounted on the steel metal plate 10. The electric motor 12 may be used as the prime mover for the apparatus, having a shaft 14 extending therefrom with a clutch member 16 disposed be tween sha-fit 14 and shaft 18, which is longitudinally aligned with shaft 14. The shaft 18 maybe provided with a braking mechanism 20, if so desired. The gear housing 22 is also mounted on the base plate 10, and contains suitable gears for transmitting the power from the horizontal shaft 18 to the vertical shaft '24. The shaft 24 has a filter basket 26 mounted thereon which may have a substantially square shape, as best shown in Figure 2. The filter basket has a cylindrical central core 28 extending upwardly from the bottom thereof which contains a collar member 30 having a central opening therein adapted to receive the tapered upper end. 32 of the vertical shafit 24. The upper extremity of the shaiit 24 is threaded and adapted to receive the locking nut 34 which secures the filter basket 26 to the vertical shafit 24. The filter basket 26 disclosed is to be rotated in a clockwise direction, as shown by the arrow in Figure 2. The filter basket 26 has a relatively open structure and may be formed so as to support any number of substantially flat filters about and substantially parallel to its axis of rotation. One of the simplest forms it may take is that which is shown in Figures 1 and 2, namely, that of an opensided square adapted to receive a single flat filter or a plurality of flat filters on each side thereof, so that the filters are held in a box-like arrangement with an open top and a substantially open bottom. Each of the corners of the filter basket may have a vertical post 36 disposed thereon with suitable bracing 37 extending between the outside edges of adjacent posts to form, together with the vertical projecting flanges 39 on each side of each post 36, the means for retaining the flat filters within the basket as the latter is rotated. Suitable means for calls ing the substantially fiat filters to retain the appropriate position in the filter basket when the basket is not rotating may also be provided, such as the spring members 38, which extend between the inner corners of adjacent vertical corner posts. Both the bracing members extending between the outside edges of the vertical corner posts 36 and the retaining members, such as springs 38 extending between the inside corners of adjacent corner posts, may be designed in such a way as to provide support for either a single large flat filter or a plurality of smaller fiat filters fitted together to form an area which is substantially the same as the area of one side of the basket between the vertical corner posts. Two smaller filters are shown in position on the left hand side of the basket, as shown in Figure l, for example.

As best shown in Figure 2, the bottom portion of the filter basket may be made up of a plurality of symmetrically disposed radial struts 40 adapted to support the outer framework of the basket and yet providing a substantially open bottom. As shown in Figures 1 and 2, a collar 41 is centrally mounted in the base of the filter basket and is adapted to be inserted in one end of the cylindrical filters, such as the filter 42, shown in Figures 1 and 2, when they are slipped over the central core 28 of the filter basket.

A cylindrical housing 44 is provided which encompasses the filter basket 26 and is open at the top and bottom. The housing 44 is supported in this position by a plurality of legs 46 which may be ofiset, as shownin Figure l, to provide room for the drain pan 48. This pan in turn is pivotally mounted on the rods 50 and 52, so that it encompasses the bottom portion of the housing 44. The rod 50 is mounted at one end of the housing 54 of the shaft 24, and at the other end on one of the supporting legs 56. The rod 52 is longitudinally aligned with the rod 50 and is also mounted at one end on the housing 54 and at the opposite end on the housing 56, which encloses the electric motor and its related components.

The circular pan 48 has a center opening 58 therein through which the housing 54 is adapted to extend, the cylindrical collar 60 around the opening 58 being of sufiicient height to extend. up into the center core 28 of the basket 26. This arrangement enables the draini'pan'48 to-be 'tilted'about the axis formed 'by the rods'S) and 52 'by Operation of the control lever 62 secured to the vertical wall 64 forming the outer "periphery of the pan 48. The two drain spouts 66 and 68 may be formed integrally with the side wall 64 of the pan 48 so that they are disposed diametrically opposite to each other on a line substantially perpendicular to the rods 50 and 52. The drain spout '66 may have associated therewith the drain 70, which may, in turn, be in communication with asewer or other means of disposal, while the drain spout 68 may have associated therewith the drain 72, in communication with the solvent reservoir. This arrangement permits the drain pan'to be tilted so that the -'contents thereof will drain either 'into the drain 70 or the drain 72, as desired. When the filters are being washed with hot water, the pan is generally tilted so as to drain through the drain spout 66, whereas when the solvent is being used, the pan is generally tilted in the opposite direction, so that the pan will drain through the drain spout '68 and the drain 72, and the solvent will be returned to the storage tank.

The housing lid 74 may be supported by the overhead air hoist 76,'so that'it'rnay be'conveniently raised 'or lowered to allow the filters'to be disposed in or removed from'the filter basket. The nozzles 'or'spray pipes 78 and 80 are supported'by the housing lid 74 in such a way as to extend vertically down into the filter basket. The spray pipe 78 is disposed so that it will be positioned between what would 'be the outer surface of a circular filter when mounted in the filter basket and the inner surface 'of the substantially flat filters mounted in the filter basket aspreviously described. The spray pipe 80 is'mounted between the center core 28 of the filter basket 26 and the inner surface of a cylindrical filter when mounted in the filter basket, as shown and described. Each of these spray pipes is closed at its lower extremity, and has a vertical line of small orifices formed therein, each of which are adapted to direct a thin stream of liquid at the filters, as indicated by the arrows 82 and 84. The upper extremities of these two spray pipesareincornmunication with 'a flexible portion of the conduit'86, which conduit is in turn connected to a-manifold 88, as shownin Figure 3.

A third spray pipe 90 of substantially the same characteras the two previously describedismounted-on the interior of thehousing 44, and is adapted to direct-a .plur'ality'of 'srnall's'treams of liquid in the direction of the arrow 92. This spray 'pipe is also connected to the conduit 86 through the pipe 91.

Referring now to Figure 3, the manifold 88 and its associated conduits are there shown somewhat diagrammatically. The pipe 94 is in communication with the manifold atone end and is connected at its opposite end to a source of hot water under pressure. It also has the valve 96 disposed therein, adjacent the manifold, for selectively controlling the input of hot water to the manifold. A pressure of 120 pounds per square inch has been found satisfactory for the hot water. The pipe 98 is also in communication with the manifold 88, and its opposite end is connected to a pump (not shown), which is in turn connected to a sump (also not shown), which may be located in any convenient position, such as below the drain pan 48. The input of the solvent to the manifold may be controlled by the valve 100 in the pipe 98. A solvent pump developing a pressure of 35 pounds per square inch has been used successfully. The pipe 102 is also in communication with the manifold 98, and at its opposite end is connected to a source of compressed air. The'valvc 104 in the pipe 102 isused to control the input of compressed air to the manifold 88..

The pipe 102 may also have the pipe 106 connected thereto providing a source. of compressed air for the operation of the overhead air hoist 76. The pipe 106 is in communication with the hoist control valve 108, which in turn controls the operation of the hoist through the pipes 110 and 112. The conduit 86 extending between the manifold 88 and the spray pipes 7 8 and 80 may have'the pipe 114 in communication therewith which in turnis connected to a high pressure oil pump 116. Thepi'pe 118 extends between the oil pump 116 and an oil reservoir (not shown). ,I

It should be understood that either the substantially flat type filters or the cylindrical type filters may be cleaned in this apparatus, but the simultaneous cleaning of both types of filters is hotpractical in the apparatus shown in the drawings. To clean the substantially flat type filters which, for example, are of a size approximately equal toone side of the-filter basket, the following steps are employed. The housing lid member 74 is lifted out of association with the housing 44 by operation of the overhead hoist 76. One of such filters is then disposed with its inner side out in each side of the filter basket between two of the vertical corner posts so that it abuts the outer frame members3 7 extending between these corner posts and the flanges 39, and is held in this position by the spring members 38. The four filters will then-form a box-like unitopen at the top and bottom, as best shown in Figure 2. The hoist control valve 108 may then be operated to lower'the housing lid member 74 into the position shown in Figure l, which in turn will cause the spray pipes 78 and '80 to also assume the position shown'in this figure. The clutch member 16 is then engag'ed so that the shaft 24 is rotated at a relatively'high speed, which in'turn causes the filter basket 26 to rotate in'the same fashion. After the basket has attained the desired speed (300 revolutions per minute has been found to be satisfactory), the valve 96 may be opened so that hot water is sprayed from all threeof the spray pipes 78,

80 and 90, infthe directionof the arrows 82, 84 and 92 respectively. In washing 'air filters from a diesel locomotive, this washing step may be continued for approximately 15 seconds. Thevalve 96 is then closed, and the valve 100 opened so that the rapidly rotating filters are then sprayed with a suitable solvent, which spray may also be continued for a period of approximately 15 seconds. Valve I00'is' then closed and valve 96 again opened for a 15 second rinse with hot water.

Following thisoperation, valve 96 is again closed and a valve 104 is opened so'that thespraypipes then direct a streamof compressedairagainst the rotating filters. This operation will cause the filters to become completely dry in a p'eriod'of approximately 15 seconds, and at the end of this period of time the oil pump 116 may be operated for a period sufiicienttoinject the required amount of oil The filters After the into the pipe 86 carrying the compressed air. are thus .giv'en a llghtic'oating of suitable oil.

{operation of the pump 116 is discontinued, the blast of the compressed air from theperforated pipes is continued for a short period in-or'der to blow off any surplus oil which may 'remain 'on thefilt'ers over and above that amountwhich is d'esirable'for proper operation of the cleaned filter. Du'ringall of the'sevarious operations, the

filter basket-has 'be'en'continu'ously rotated at a relatively high speed, but after the surplus'oil' is blown off the clutch 16maybedisengaged, and the brake 23 operated. The frame lid 74 may then be raised and the cleaned filters removed to 'makew'ayfor are'petition of the process on a new batch of filters.

Duringthe first washing step, in which 'a'rathe'r high percentage 'of the foreign material is removed from the filter, the drain pan 48 may be tilted by operation of the control member 62'so that the drain spout 66 is brought 'into close association with the'drain and the hot water containing thedirt and other undesirable'material is disposed of as waste through this latter drain. Prior to beginning th'e app'lication ofthe'hot solvent, however, the

drain pan 48-is'tilted in'the opposite direction by operation of the control member 62, 'so that the operation of the dram spout 68 is brought into close association with the drain 72and'the's'olvent is thus returned to the sump from which it was initially drawn by the solvent pump.

Again priorto the rinsing step, the drain pan 48 may be returned to the position-in which the drain spout 66 is brought into close'association with the drain 70, and the rinse "water may then be passed off as waste material.

Although the various liquids are projected from. the

spray 'pipes 'with considerable force, it has been noted from the actual operation of the apparatus disclosed that the centrifugal force generated by the relatively rapid rotation 'of 'the filtersis such that it contributes greatly to the cleanin'g'action of the liquids utilized. Assuming a clockwise rotation-of the filter basket 26, as viewed in Figure 2 although'the spray pipes 79 and are arranged so as to project the streams of liquid in a way which does not substantially oppose the centrifugal forces generated, the spray pipe 90 is shown disposed so as to spray in a direction substantially contrary to that in which the centrifugal force will tend to throw fluid material once it is in association With the rapidly rotating filters. This disposition of the spray pipe 90 has been found to be advantageous, since its primary purpose is to aid in removing the undesirable material from the outer face of the filter as it is forced out from the interior of the filter by the action of the spray pipes 78 and 80, and also by the centrifugal force generated by the rotation of the filters.

As previously stated, the entire cleaning operation which previously consumed about 6 hours per filter can now be carried out utilizing this apparatus so that approximately 2 minutes per filter is required. This results, of course, in a very substantial saving, and, in the case of locomotive filters, also eliminates the necessity for keeping a spare set of filters on hand with which to replace those which are being cleaned. In other words, the time for cleaning has been so reduced that the opera tion can be carried out in the normal time allowed for reconditioning the locomotive when it is not actually being taken out of operation for overhauling.

With respect to the cleaning of cylindrical filters, the process is substantially the same as described for the cleaning of the substantially fiat filters. One end of the cylindrical filter is disposed on the collar 41, and during the cleaning steps the spray pipes 78 and 80 function in substantially the same way as the spray pipes 78 and 90 function respectively during the cleaning of the flat filters. A valve may be provided for shutting off the spray pipe 90 during the cleaning of cylindrical filters if desired, since it will contribute very little to the operation. The same sequence of steps is followed in the cleaning of a cylindrical filter as described above, and the results achieved are equally as desirable.

The drawing and the above discussion are not intended to represent the only possible form of this invention, in regard to details of construction. Changes in form and in the proportion of parts, as Well as the substitution of equivalents are contemplated, as circumstances may suggest or render expedient, without departing from the spirit or scope of this invention, as further defined in the following claims.

What is claimed is:

l. A filter cleaning device comprising a rotatable basket, said basket being adapted to hold a plurality of substantially fiat filters in abutting relationship with the sides of said basket by means of centrifugal force when said basket is rotated, means for rotating said basket, said basket being mounted on said means, a forked supply pipe disposed in substantially parallel relationship to the axis of rotation of said basket, a plurality of spraying means in the forks of said pipe adapted to project filter cleaning elements against said filters at substantially a right angle to the vertical plane of said filters, an enclosing shield for said basket and said spray means, a manually tiltable receptacle enclosing the base of said shield having a drain opening on each side of the axis about which said receptacle tilts.

2. A filter cleaning device comprising an externally braced upright basket member of substantially open construction centrally mounted at its base on a rotatable sup porting axis, said axis being adapted to be activated at one end thereof, said basket member being adapted to support a plurality of symmetrically disposed substantially flat filters each substantially normal to a radial line extending from said supporting axis, a single non-rotatable enclosing chamber for said basket, a supply pipe disposed in substantially perpendicular relationship to the top of said chamber, and a plurality of directional spray pipes branching from said supply pipe and disposed substantially parallel to the axis of rotation of said basket member within said basket member adapted to spray liquid and gaseous substances as desired against the inner surfaces of said filters at substantially a right angle to the vertical planes thereof under substantial pressure so that the passage of said liquid and gaseous substances through said filters is insured by the operation of centrifugal force, and a manually tiltable receptacle at the base of said housing for collecting and selectively distributing said fluid substances.

3. A filter cleaning device comprising an externally braced upright basket member of substantially open construction centrally mounted at its base on a rotatable supporting axis, said axis being adapted to be activated at one end thereof, said basket member being adapted to support a plurality of symmetrically disposed substantially fiat filters each substantially normal to a radial line extending from said supporting axis, a single non-rotatable enclosing chamber for said basket, a supply pipe disposed in substantially perpendicular relationship to the top of said chamber, and a plurality of directional spray pipes branching from said supply pipe and disposed substantially parallel to the axis of rotation of said basket member within said basket member adapted to spray liquid and gaseous substances as desired against the inner surfaces of said filters at substantially a right angle to the vertical planes thereof under substantial pressure so that the passage of said liquid and gaseous substances through said filters is insured by the operation of centrifugal force, and a manually tiltable receptacle enclosing the base of said housing member having a drain opening on each side of the axis about which said receptacle tilts.

References Cited in the file of this patent UNITED STATES PATENTS 1,197,324 Wright Sept. 5, 1916 1,405,243 Wing Jan. 31, 1922 1,435,172 Masonick Nov. 14, 1922 1,670,611 Couch May 22, 1928 1,712,751 Cunningham May 14, 1929 2,178,701 Petre Nov. 7, 1939 2,249,521 Graham et a1. July 15, 1941 2,256,663 Brewer Sept. 23, 1941 2,508,999 Hirsch May 23, 1950 

